SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e6e6f6afa9c96dec460aca9631ebe89462948139165068057d7cfc83464aa884' 
  AND token = 'TDtjVBDTKVTVHa96ybTVQmM+Myljf6Tv4DOOl/kG/EY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}